Process of making phenols.



H. S. KHVIBALL.

PROCESS 0F MAKING PHENOLS.

APPLICATION FILED luLY 24.191,5.

lltented-lhnr. 6, 1917.

UNITED sTaTas PATENT OFFICE.,

-. HERBERT S..3KIMBALL, 9F NEWTQJS', -MASSACHUSETTS,BSSIG-NOR IT0-ILII-Illtltl'.AC

=GHEMICAL COMPANY; 10F BOS'EONJMASSACHUSETTS, A-EGORPORATION OF-MASSA- GHUSETTS.

PROGESS 0F MAKING PHENOLS.

To all whom it may concern:

a citizen of the United States, residing at- Newton, in the county =of""MiddleseX and State of Massachusetts, have invented certain new and useful Improvements' in.J Processes of Making Phenols, of which the following is a speciiication. i

According to the present invention phenols are prepared from the corresponding aromatic hydrocarbons, as phenol from benzol, by a cyclical process which is an improvement upon that described in a copendin application of Henry Howard, Serial o. 29,825,1iled May 22. 1915.

The present invention may be carried out as follows: The benzol is first sulfonated as usual, and the resulting sulfonic acid compound, containing an excess of sulfuric acid, is wholly or partly neutralized by calcium sulte, utilizing for this purpose the calcium sulite which is produced at a. later stage of the cyclical process, as explained below. The neutralization is effected in closed tanks, and the evolved sulfur dioXid, or such portion. thereof as may be required, is employed to Boom ose the sodium phenolate as described in t e above mentioned application. In case the quantity of calcium sulte available is insuiL' cient for complete neutralization of the sulfonic acid compound, it is supplemented by lime or limestone. l

The calcium benzol sulfonate prepared as above is treated with the molecular equivalent Vof sodium sulfite, and is thereby transformed into sodium benzolk sulfonate. The

Sodium suliite may be Iintroduced either in,

solution or in solid form into the solution of calcium benzol sulfonate, and the calcium sulfite which separates .out is applied toward the neutralization of the sulfonic acid compound produced in` the first step of the process. A

The sodium benzol sulfonate is now subjected to a caustic fusion to produce sodium; phenolate, which in turn is decomposed by sulfur dioxid (undiluted) arislng from the neutralization step of the process. The phenol is deca-nted, andthe remainin liquor, containing sodium sulfite or bisu ite or a` mixture of these is utilized in 'part for the conversion of the calcium benzol sulfonate .into the corresponding sodium salt as above described, and is in part Specification of `Letters Patent.

phenol from the Ifatented Nov. 6, :1917.

' application-mea July-.24, 1915. 1i serial No. 41,659.

causticized by flime,yielding a dilute ycaustic soda solution, and calcium sulfite, thelatter available for-1 neutralizing'lthe benzol' v sulfonic aid.- If'desiredftl1e5-caustic'-.sodasolution may be concentrated and returned to the cycle.

A" complete cycle embodying the invention is shown on the accompanying diagram. It is to be understood however that the present invention is not limited to the performance of the comple-te cycle as thereinr indicated, but relates more particularly to the utilization of sodium sulfite for converting calcium benzol sulfonate into sodium benzol sulfonate, as a step preceding the usual caustic fusion for the production of phenolate. This conversion is of course particularly advantageous in conjunction with the employment of sulfur dioxid to liberate the phenolate, as disclosed in the'said Howard application, inasmuch as the sodium sulte required is thereby pro- .duced in the regular operation of the process.

While I have explained my process with specific reference to the preparation of phenol from benzol, it is to be understood that the invention is not restricted to this particular reaction, but is applicable in the production of phenols in genera-lefrom the corresponding aromatic hydrocarbons.

I claim l 1. In a process of making phenols from the corresponding aromatic hydrocarbons, the steps which consist in' sulfonating the hydrocarbon, neutralizing the sulfonic acid compound by a calcium compound, and

-compound into the corresponding sodium salt by means of sodium sulfite.

2. Ina process of makingphenols from the corresponding aromatic hydrocarbons, the steps which consist in sulfonating the hydrocarbon, neutralizingl the sulfonic acid compound b calcium sul te, and transforming the resu ting calcium sulfonic compound into the corres of sodium sul te.

3. In a process of makingphenols from the corresponding aromatic hydrocarbons, the steps which. consist in sulfonating the hydrocarbon, neutralizing the sulfonic acid compound by of sulfur dioxid, transforming the resulting calcium sulfonic compound into the corre-- onding sodium salt by means i calcium sulfite with evolution sponding sodium salt by meansv of sodium sullite, and utilizing the sulfur dioxid evolved during the neutralization for the preparation of sodium sulite.

4. A cyclical process of making phenols from the corresponding aromatic hydrocarbons, which consists in sulfonating the hydrocarbon, neutralizing the sulfonic acld compound by calcium sulfite with evolution of sulfur dioxid, transforming the resulting calcium sulfonic compoundy into the correspending sodium salt by means of sodium sulite, converting the sodium salt into plie nolate by treating the same With .caustic soda,`

' rua/lasse and liberating phenol from the phenolate with simultaneous production of sodium sulite by reacting thereon with. the sulfur dioX-id evolved during the neutralization.

5. 1n a process of the character described, the step which consists in reacting with sodiuln sulite on calcium benzol sulfonate.

lin testimony whereof l aiix my signature in presence of tWo witnesses.

LEON E. AMBROSE, HAROLD A. PEER. 

